9x43 - Fairy Tail

As the Christina outmaneuvers Acnologia, Wendy recognizes the blonde-haired woman as Anna, who traveled into the present through Eclipse with her and the other Dragon Slayers as their childhood tutor. Anna and Blue Pegasus reveal their plan to trap Acnologia within an inescapable rift in time created as a side effect of using Eclipse. Meanwhile, Natsu's friends determine that they must open the Book of E.N.D. to save Natsu. After incapacitating Natsu, Zeref reveals his plan to perform Neo Eclipse, a spell designed to reset time so that he never becomes immortal and Acnologia is killed, which threatens to erase the current timeline in the process, and requires the power of Fairy Heart and the time rift.